Liquid crystal displays have currently become a major technology due to advantages such as a low power consumption, a low driving voltage, being easy to drive, direct driving of an available large scale integrated circuit, a simple structure etc.
As shown in FIG. 1, a conventional liquid crystal display generally includes a liquid crystal display panel 01, a source driver 02, a gate driver 03, an interface connector 04, a switching power supply (DC/DC) 05 and a clock controller 06. The clock controller 06 is configured to convert a digital video image signal (LVDS) output by the interface connector into a ClocK control Horizontally (CKH) signal, a Synchronizing Time Horizontally (STH) signal, a Reduced Swing Differential Signal (RSDS) and a POLarity inversion control signal (POL) etc. required for operation of the source driver 02 and control a polarity inversion mode of an image displayed on the liquid crystal display panel 01. The switching power supply 05 is configured to convert a unconverted power supply voltage (VDD) output by the interface connector 04 into various voltages complying with respective operation requirements of the clock controller 06. The liquid crystal display panel 01 and the above various components cooperate with each other to implement display of image.
With a development of the liquid crystal display technology, a load of the liquid crystal display becomes larger. A conventional switching power supply may possibly have a higher temperature or even be damaged due to overload. Especially when a complex picture is displayed, the liquid crystal display will have a very large load, and both operating current and power consumption of the switching power supply are large under a heavy load at this time, thereby resulting in the switching power supply having a higher temperature or even being damaged due to the higher temperature.